Pro's of tube over bottel and shot count?

I believe one of the main advantages to a tube PCP is that you can hand pump a lot of them. No HPA compressor needed.

It’s just volume of air. Bigger tank takes longer to fill, higher pressure takes more effort. So the rifles with tubes at lower pressure have lower volume and lower effort for a hand pump. Same size tube and bottle at the same pressure will be the same effort to pump.